A Japanese Olympic medalist has admitted causing a collision that injured several people last month in Nara Prefecture, western Japan, investigative sources said Wednesday.

He is suspected of fleeing the scene despite the driver of the other vehicle, a 40-year-old woman, sustaining minor injuries.

Police plan to send prosecutors papers about the case involving Taku Hiraoka, a 23-year-old Japanese snowboarder who won bronze in the men's halfpipe at the 2014 Winter Olympics in Sochi, Russia.

Hiraoka, who had been drinking the night before the accident, explained he "confused the accelerator and the brake" when driving in Katsuragi on Sept. 29, sources close to the matter said. Police are investigating whether he was under the influence of alcohol.

According to investigators, Hiraoka, who hails from the neighboring city of Gose, hit a minicar around 9:55 a.m.

The impact of the crash caused the minicar to run onto a sidewalk, hitting a 4-year-old boy and three other people in their 30s and 40s, all of whom sustained minor injuries.

Police questioned Hiraoka on the day of the accident.